Aims & Objectives:
This is the first investigational study in Pediatric ARDS using CT scan to assess “potential for lung recruitment” after bedside PEEP-titration.
The one-year study period had 38 children with moderate to severe ARDS as per PALISI definition, of them 18 were excluded due to clinical instability (14 HFOV, 8 with air leaks, multiple inotropes). The study group (n=20) underwent PEEP titration using P-V loop while on Pressure-Control mode. Using same ventilator settings, they were connected to the appropriately calibrated transport ventilator, and were shifted for five dual-slice varying-intervals protocol CT scan. Lung area was calculated with a software and based on Hounsfield Units was divided into non-aerated (+100 to -100), poorly-aeriated (-100 to -500), well-aeriated (-500 to -900) and hyper-inflated (-900 to -1000).
PEEP titration achieved significant improvement in SpO2/FiO2 ratio (p=0.0001) and optimum lung compliance. After PEEP titration, average “well-aerated area” was more (57.88%) in Indirect ARDS than Direct ARDS (46.01%) but this was not statistically significant (p=0.184). In-spite of optimum bed-side PEEP titration, average “potential for recruitment” area was 52.64% and 42.03% in indirect and direct ARDS respectively. Radiation exposure in the study group by using five-slice protocol was significantly lower when compared with children from same age group who got chest CT scans for other reasons (0.6657 Vs 1.6484 p=0.0001).
Bed-side PEEP titration achieved significant improvement in oxygenation and optimum lung compliance. However, CT scan revealed 42–52% lung with “potential for recruitment”. Five-slice CT protocol resulted in significantly less radiation exposure.